A simple and high yield synthesis of radiolabeled 1-O-valproyl-β-D-glucopyranuronic acid was developed with the use of UDP-glucuronosyltransferase. Valproic acid, UDP-glucuronic acid, and UDP-glucuronosyltransferase were incubated for 48h at an optimum pH of 8.5. The enzymatic synthesis followed by column purification gave 51.8% and 52.5% yields of14C- and3H- labeled 1-O-valproyl-β-D-glucopyranuronic acid, respectively. The radiochemical purities of the14C- and3H-labeled substances were 98.8% and 99.2%, respectively. In contrast, the chemical synthesis using 2, 3, 4, 6-tetrabenzyl-D-glucopyranose and valproic acid resulted in much lower yield (6.8%) .
54Mn is one of the activation products generated in nuclear reactors. This study was carried out to find a method appropriate for the removal of54Mn. Intraperitoneal administration of stable manganese effectively promoted the excretion of54Mn from the mouse body. The efficacy for removing54Mn was estimated to be 56, 67, 77 and 82% for manganese doses of 0.3, 1, 3 and 10mg/ kg, respectively. Oral administration of stable manganese was also effective for the removal of54Mn, but the efficacy was inferior to that obtained by intraperitoneal administration because of low gastrointestinal absorption of manganese. Ca-DTPA and Zn-DTPA promoted the excretion of54Mn when administered 1 h after administration of54Mn, but these chelating agents had little effect when administered after 3 h or more. Zn-DTPA was less effective than Ca-DTPA. These results demonstrate that dilution with stable manganese is more effective than Chelation with DTPA for the removal of54Mn from the body.
222Rn concentrations were simultaneously measured at a beranda (outdoor) and a room (indoor) of a tall apartment for a week. Average222Rn concentrations at the outdoor and indoor were 3.25 Bq/m3 and 19.8 Bq/m3, respectively. Correlation analysis showed significant negative relation between outdoor222Rn concentration and wind velocity as well as wind directions from south and west. There observed a significant positive relation between indoor and outdoor222Rn concentration as well as a negative relation between indoor222Rn concentration and wind direction from west.